ANDY WIGHTMAN MSP AND OTHERS vs SECRETARY OF STATE FOR EXITING THE EUROPEAN UNION
doesn't do that.

The "constitutional" question about EU jurisdiction is very narrow: whether ECJ scope of  "supervisory jurisdiction" (advisory function, "Declarator") reaches Scotland's Court of Sessions judgment of disputed separation of powers in UK gov. The SCS settled that constitutional question for MSPs. The question

whether a notice given by a member state in terms of Article 50 may competently be revoked unilaterally before the expiry of the two year period.

concerns events which have not occurred and which SCS would not endorse because "It appears that there is no authority, in Scotland, England or the EU, directly in point on this issue". No UK, no EU procedure to revoke the A50 action. There are none. So, no unilateral effect.

We know, after 31 March 2019, UK might as well simply re-apply for membership. This right is not controversial but in no way simplifies UK procedural chaos.

ECJ accepted the review opportunity in order to affirm, zero interest in creating procedural law for UK revoking A50 notice (observing EU own separation of powers) and limited interests in adjudicating members' nonconforming laws with EU directives. ECJ will affirm UK sovereignty and SCS authority to remand MSPs, I predict. Doing so explicitly establishes EU legal precedent for the issues.

MSPs should have invoked some Art.7 issues and EU case law to stimulate the desired remedy.

Diversity is the key to economic and political evolution.